A friend of mine just got an office-issued black Macbook and he mentioned dual-booting it with Mac OS X and Ubuntu via ReFiT. Whilst there is nothing wrong doing it, I just do not see the point unless you really hate using the BSD-based Mac OS X and its eye-candy. Ironic, but Linux is being beefed up with more eye-candy as well.
Anyway, if you have a Macbook and wish to run Ubuntu natively, you might want to check out these two documents. Remember that not all features are natively supported, specially if you have the latest Macbooks.
Again, I do not see the point when Linux runs just fast as a guest OS on. Oh well, to each his own! :)
Image from Flickr:Galaygobi.